.header{
  height: 30px;
  background: greenyellow;
  display: flex;
  position: relative;
  align-items: center;
  .left{
    margin-left: 10px;
    flex: 1;
  }
  .title{
    flex: 5;
    text-align: center;
    margin: 0 20px;
    // 设置文本超出隐藏
    overflow: hidden;
    white-space: nowrap;
    text-overflow: ellipsis;
  }
  .right{
    margin-right: 10px;
    flex: 1;
  }

}